408 spark plugs

At 11:1 I don't run that plug. Unless you are over that CR you need a 12 champion. And, FWIW I never buy the N series plugs any more. There is no reason for that gigantic 13/16 hex. You can use the RC12YC plug and it has a 5/8 hex instead of the elephant size of the N series.

As for the back two plugs...my best tip is since you have manual steering, I'd order a set of Hooker 5204's and never look back. They are a PITA to get in, but once installed you can get to all the plugs and they make as much or more power than the rest of that cheap crap that blocks the 5 and 7 plugs.

Ok, if you're not up for changing headers (I'd seriously consider it not exclusions the above mentioned PITA part and the extra expense) you need to get at the plugs any way you can. Some guys pull the tire and sneak In there. I have a socket with a universal built in, or you can get a sperate universal.

It's a beeeeeeeotch with those headers. You have to do what you have to do and there's no wrong way to do it. Unless you break something.